linux/drivers/firmware/qcom_scm.c

// SPDX-License-Identifier: GPL-2.0-only
/* Copyright (c) 2010,2015,2019 The Linux Foundation. All rights reserved.
 * Copyright (C) 2015 Linaro Ltd.
 */
#include <linux/platform_device.h>
#include <linux/init.h>
#include <linux/cpumask.h>
#include <linux/export.h>
#include <linux/dma-direct.h>
#include <linux/dma-mapping.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/qcom_scm.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_platform.h>
#include <linux/clk.h>
#include <linux/reset-controller.h>
#include <linux/arm-smccc.h>

#include "qcom_scm.h"

static bool download_mode = IS_ENABLED(CONFIG_QCOM_SCM_DOWNLOAD_MODE_DEFAULT);
module_param(download_mode, bool, 0);

#define SCM_HAS_CORE_CLK	BIT(0)
#define SCM_HAS_IFACE_CLK	BIT(1)
#define SCM_HAS_BUS_CLK		BIT(2)

struct qcom_scm {
	struct device *dev;
	struct clk *core_clk;
	struct clk *iface_clk;
	struct clk *bus_clk;
	struct reset_controller_dev reset;

	u64 dload_mode_addr;
};

struct qcom_scm_current_perm_info {
	__le32 vmid;
	__le32 perm;
	__le64 ctx;
	__le32 ctx_size;
	__le32 unused;
};

struct qcom_scm_mem_map_info {
	__le64 mem_addr;
	__le64 mem_size;
};

#define QCOM_SCM_FLAG_COLDBOOT_CPU0	0x00
#define QCOM_SCM_FLAG_COLDBOOT_CPU1	0x01
#define QCOM_SCM_FLAG_COLDBOOT_CPU2	0x08
#define QCOM_SCM_FLAG_COLDBOOT_CPU3	0x20

#define QCOM_SCM_FLAG_WARMBOOT_CPU0	0x04
#define QCOM_SCM_FLAG_WARMBOOT_CPU1	0x02
#define QCOM_SCM_FLAG_WARMBOOT_CPU2	0x10
#define QCOM_SCM_FLAG_WARMBOOT_CPU3	0x40

struct qcom_scm_wb_entry {
	int flag;
	void *entry;
};

static struct qcom_scm_wb_entry qcom_scm_wb[] = {
	{ .flag = QCOM_SCM_FLAG_WARMBOOT_CPU0 },
	{ .flag = QCOM_SCM_FLAG_WARMBOOT_CPU1 },
	{ .flag = QCOM_SCM_FLAG_WARMBOOT_CPU2 },
	{ .flag = QCOM_SCM_FLAG_WARMBOOT_CPU3 },
};

static const char *qcom_scm_convention_names[] = {
	[SMC_CONVENTION_UNKNOWN] = "unknown",
	[SMC_CONVENTION_ARM_32] = "smc arm 32",
	[SMC_CONVENTION_ARM_64] = "smc arm 64",
	[SMC_CONVENTION_LEGACY] = "smc legacy",
};

static struct qcom_scm *__scm;

static int qcom_scm_clk_enable(void)
{
	int ret;

	ret = clk_prepare_enable(__scm->core_clk);
	if (ret)
		goto bail;

	ret = clk_prepare_enable(__scm->iface_clk);
	if (ret)
		goto disable_core;

	ret = clk_prepare_enable(__scm->bus_clk);
	if (ret)
		goto disable_iface;

	return 0;

disable_iface:
	clk_disable_unprepare(__scm->iface_clk);
disable_core:
	clk_disable_unprepare(__scm->core_clk);
bail:
	return ret;
}

static void qcom_scm_clk_disable(void)
{
	clk_disable_unprepare(__scm->core_clk);
	clk_disable_unprepare(__scm->iface_clk);
	clk_disable_unprepare(__scm->bus_clk);
}

static int __qcom_scm_is_call_available(struct device *dev, u32 svc_id,
					u32 cmd_id);

enum qcom_scm_convention qcom_scm_convention;
static bool has_queried __read_mostly;
static DEFINE_SPINLOCK(query_lock);

static void __query_convention(void)
{
	unsigned long flags;
	struct qcom_scm_desc desc = {
		.svc = QCOM_SCM_SVC_INFO,
		.cmd = QCOM_SCM_INFO_IS_CALL_AVAIL,
		.args[0] = SCM_SMC_FNID(QCOM_SCM_SVC_INFO,
					   QCOM_SCM_INFO_IS_CALL_AVAIL) |
			   (ARM_SMCCC_OWNER_SIP << ARM_SMCCC_OWNER_SHIFT),
		.arginfo = QCOM_SCM_ARGS(1),
		.owner = ARM_SMCCC_OWNER_SIP,
	};
	struct qcom_scm_res res;
	int ret;

	spin_lock_irqsave(&query_lock, flags);
	if (has_queried)
		goto out;

	qcom_scm_convention = SMC_CONVENTION_ARM_64;
	// Device isn't required as there is only one argument - no device
	// needed to dma_map_single to secure world
	ret = scm_smc_call(NULL, &desc, &res, true);
	if (!ret && res.result[0] == 1)
		goto out;

	qcom_scm_convention = SMC_CONVENTION_ARM_32;
	ret = scm_smc_call(NULL, &desc, &res, true);
	if (!ret && res.result[0] == 1)
		goto out;

	qcom_scm_convention = SMC_CONVENTION_LEGACY;
out:
	has_queried = true;
	spin_unlock_irqrestore(&query_lock, flags);
	pr_info("qcom_scm: convention: %s\n",
		qcom_scm_convention_names[qcom_scm_convention]);
}

static inline enum qcom_scm_convention __get_convention(void)
{
	if (unlikely(!has_queried))
		__query_convention();
	return qcom_scm_convention;
}

/**
 * qcom_scm_call() - Invoke a syscall in the secure world
 * @dev:	device
 * @svc_id:	service identifier
 * @cmd_id:	command identifier
 * @desc:	Descriptor structure containing arguments and return values
 *
 * Sends a command to the SCM and waits for the command to finish processing.
 * This should *only* be called in pre-emptible context.
 */
static int qcom_scm_call(struct device *dev, const struct qcom_scm_desc *desc,
			 struct qcom_scm_res *res)
{
	might_sleep();
	switch (__get_convention()) {
	case SMC_CONVENTION_ARM_32:
	case SMC_CONVENTION_ARM_64:
		return scm_smc_call(dev, desc, res, false);
	case SMC_CONVENTION_LEGACY:
		return scm_legacy_call(dev, desc, res);
	default:
		pr_err("Unknown current SCM calling convention.\n");
		return -EINVAL;
	}
}

/**
 * qcom_scm_call_atomic() - atomic variation of qcom_scm_call()
 * @dev:	device
 * @svc_id:	service identifier
 * @cmd_id:	command identifier
 * @desc:	Descriptor structure containing arguments and return values
 * @res:	Structure containing results from SMC/HVC call
 *
 * Sends a command to the SCM and waits for the command to finish processing.
 * This can be called in atomic context.
 */
static int qcom_scm_call_atomic(struct device *dev,
				const struct qcom_scm_desc *desc,
				struct qcom_scm_res *res)
{
	switch (__get_convention()) {
	case SMC_CONVENTION_ARM_32:
	case SMC_CONVENTION_ARM_64:
		return scm_smc_call(dev, desc, res, true);
	case SMC_CONVENTION_LEGACY:
		return scm_legacy_call_atomic(dev, desc, res);
	default:
		pr_err("Unknown current SCM calling convention.\n");
		return -EINVAL;
	}
}

static int __qcom_scm_is_call_available(struct device *dev, u32 svc_id,
					u32 cmd_id)
{
	int ret;
	struct qcom_scm_desc desc = {
		.svc = QCOM_SCM_SVC_INFO,
		.cmd = QCOM_SCM_INFO_IS_CALL_AVAIL,
		.owner = ARM_SMCCC_OWNER_SIP,
	};
	struct qcom_scm_res res;

	desc.arginfo = QCOM_SCM_ARGS(1);
	switch (__get_convention()) {
	case SMC_CONVENTION_ARM_32:
	case SMC_CONVENTION_ARM_64:
		desc.args[0] = SCM_SMC_FNID(svc_id, cmd_id) |
				(ARM_SMCCC_OWNER_SIP << ARM_SMCCC_OWNER_SHIFT);
		break;
	case SMC_CONVENTION_LEGACY:
		desc.args[0] = SCM_LEGACY_FNID(svc_id, cmd_id);
		break;
	default:
		pr_err("Unknown SMC convention being used\n");
		return -EINVAL;
	}

	ret = qcom_scm_call(dev, &desc, &res);

	return ret ? : res.result[0];
}

/**
 * qcom_scm_set_warm_boot_addr() - Set the warm boot address for cpus
 * @entry: Entry point function for the cpus
 * @cpus: The cpumask of cpus that will use the entry point
 *
 * Set the Linux entry point for the SCM to transfer control to when coming
 * out of a power down. CPU power down may be executed on cpuidle or hotplug.
 */
int qcom_scm_set_warm_boot_addr(void *entry, const cpumask_t *cpus)
{
	int ret;
	int flags = 0;
	int cpu;
	struct qcom_scm_desc desc = {
		.svc = QCOM_SCM_SVC_BOOT,
		.cmd = QCOM_SCM_BOOT_SET_ADDR,
		.arginfo = QCOM_SCM_ARGS(2),
	};

	/*
	 * Reassign only if we are switching from hotplug entry point
	 * to cpuidle entry point or vice versa.
	 */
	for_each_cpu(cpu, cpus) {
		if (entry == qcom_scm_wb[cpu].entry)
			continue;
		flags |= qcom_scm_wb[cpu].flag;
	}

	/* No change in entry function */
	if (!flags)
		return 0;

	desc.args[0] = flags;
	desc.args[1] = virt_to_phys(entry);

	ret = qcom_scm_call(__scm->dev, &desc, NULL);
	if (!ret) {
		for_each_cpu(cpu, cpus)
			qcom_scm_wb[cpu].entry = entry;
	}

	return ret;
}
EXPORT_SYMBOL(qcom_scm_set_warm_boot_addr);

/**
 * qcom_scm_set_cold_boot_addr() - Set the cold boot address for cpus
 * @entry: Entry point function for the cpus
 * @cpus: The cpumask of cpus that will use the entry point
 *
 * Set the cold boot address of the cpus. Any cpu outside the supported
 * range would be removed from the cpu present mask.
 */
int qcom_scm_set_cold_boot_addr(void *entry, const cpumask_t *cpus)
{
	int flags = 0;
	int cpu;
	int scm_cb_flags[] = {
		QCOM_SCM_FLAG_COLDBOOT_CPU0,
		QCOM_SCM_FLAG_COLDBOOT_CPU1,
		QCOM_SCM_FLAG_COLDBOOT_CPU2,
		QCOM_SCM_FLAG_COLDBOOT_CPU3,
	};
	struct qcom_scm_desc desc = {
		.svc = QCOM_SCM_SVC_BOOT,
		.cmd = QCOM_SCM_BOOT_SET_ADDR,
		.arginfo = QCOM_SCM_ARGS(2),
		.owner = ARM_SMCCC_OWNER_SIP,
	};

	if (!cpus || (cpus && cpumask_empty(cpus)))
		return -EINVAL;

	for_each_cpu(cpu, cpus) {
		if (cpu < ARRAY_SIZE(scm_cb_flags))
			flags |= scm_cb_flags[cpu];
		else
			set_cpu_present(cpu, false);
	}

	desc.args[0] = flags;
	desc.args[1] = virt_to_phys(entry);

	return qcom_scm_call_atomic(__scm ? __scm->dev : NULL, &desc, NULL);
}
EXPORT_SYMBOL(qcom_scm_set_cold_boot_addr);

/**
 * qcom_scm_cpu_power_down() - Power down the cpu
 * @flags - Flags to flush cache
 *
 * This is an end point to power down cpu. If there was a pending interrupt,
 * the control would return from this function, otherwise, the cpu jumps to the
 * warm boot entry point set for this cpu upon reset.
 */
void qcom_scm_cpu_power_down(u32 flags)
{
	struct qcom_scm_desc desc = {
		.svc = QCOM_SCM_SVC_BOOT,
		.cmd = QCOM_SCM_BOOT_TERMINATE_PC,
		.args[0] = flags & QCOM_SCM_FLUSH_FLAG_MASK,
		.arginfo = QCOM_SCM_ARGS(1),
		.owner = ARM_SMCCC_OWNER_SIP,
	};

	qcom_scm_call_atomic(__scm ? __scm->dev : NULL, &desc, NULL);
}
EXPORT_SYMBOL(qcom_scm_cpu_power_down);

int qcom_scm_set_remote_state(u32 state, u32 id)
{
	struct qcom_scm_desc desc = {
		.svc = QCOM_SCM_SVC_BOOT,
		.cmd = QCOM_SCM_BOOT_SET_REMOTE_STATE,
		.arginfo = QCOM_SCM_ARGS(2),
		.args[0] = state,
		.args[1] = id,
		.owner = ARM_SMCCC_OWNER_SIP,
	};
	struct qcom_scm_res res;
	int ret;

	ret = qcom_scm_call(__scm->dev, &desc, &res);

	return ret ? : res.result[0];
}
EXPORT_SYMBOL(qcom_scm_set_remote_state);

static int __qcom_scm_set_dload_mode(struct device *dev, bool enable)
{
	struct qcom_scm_desc desc = {
		.svc = QCOM_SCM_SVC_BOOT,
		.cmd = QCOM_SCM_BOOT_SET_DLOAD_MODE,
		.arginfo = QCOM_SCM_ARGS(2),
		.args[0] = QCOM_SCM_BOOT_SET_DLOAD_MODE,
		.owner = ARM_SMCCC_OWNER_SIP,
	};

	desc.args[1] = enable ? QCOM_SCM_BOOT_SET_DLOAD_MODE : 0;

	return qcom_scm_call(__scm->dev, &desc, NULL);
}

static void qcom_scm_set_download_mode(bool enable)
{
	bool avail;
	int ret = 0;

	avail = __qcom_scm_is_call_available(__scm->dev,
					     QCOM_SCM_SVC_BOOT,
					     QCOM_SCM_BOOT_SET_DLOAD_MODE);
	if (avail) {
		ret = __qcom_scm_set_dload_mode(__scm->dev, enable);
	} else if (__scm->dload_mode_addr) {
		ret = qcom_scm_io_writel(__scm->dload_mode_addr,
				enable ? QCOM_SCM_BOOT_SET_DLOAD_MODE : 0);
	} else {
		dev_err(__scm->dev,
			"No available mechanism for setting download mode\n");
	}

	if (ret)
		dev_err(__scm->dev, "failed to set download mode: %d\n", ret);
}

/**
 * qcom_scm_pas_init_image() - Initialize peripheral authentication service
 *			       state machine for a given peripheral, using the
 *			       metadata
 * @peripheral: peripheral id
 * @metadata:	pointer to memory containing ELF header, program header table
 *		and optional blob of data used for authenticating the metadata
 *		and the rest of the firmware
 * @size:	size of the metadata
 *
 * Returns 0 on success.
 */
int qcom_scm_pas_init_image(u32 peripheral, const void *metadata, size_t size)
{
	dma_addr_t mdata_phys;
	void *mdata_buf;
	int ret;
	struct qcom_scm_desc desc = {
		.svc = QCOM_SCM_SVC_PIL,
		.cmd = QCOM_SCM_PIL_PAS_INIT_IMAGE,
		.arginfo = QCOM_SCM_ARGS(2, QCOM_SCM_VAL, QCOM_SCM_RW),
		.args[0] = peripheral,
		.owner = ARM_SMCCC_OWNER_SIP,
	};
	struct qcom_scm_res res;

	/*
	 * During the scm call memory protection will be enabled for the meta
	 * data blob, so make sure it's physically contiguous, 4K aligned and
	 * non-cachable to avoid XPU violations.
	 */
	mdata_buf = dma_alloc_coherent(__scm->dev, size, &mdata_phys,
				       GFP_KERNEL);
	if (!mdata_buf) {
		dev_err(__scm->dev, "Allocation of metadata buffer failed.\n");
		return -ENOMEM;
	}
	memcpy(mdata_buf, metadata, size);

	ret = qcom_scm_clk_enable();
	if (ret)
		goto free_metadata;

	desc.args[1] = mdata_phys;

	ret = qcom_scm_call(__scm->dev, &desc, &res);

	qcom_scm_clk_disable();

free_metadata:
	dma_free_coherent(__scm->dev, size, mdata_buf, mdata_phys);

	return ret ? : res.result[0];
}
EXPORT_SYMBOL(qcom_scm_pas_init_image);

/**
 * qcom_scm_pas_mem_setup() - Prepare the memory related to a given peripheral
 *			      for firmware loading
 * @peripheral:	peripheral id
 * @addr:	start address of memory area to prepare
 * @size:	size of the memory area to prepare
 *
 * Returns 0 on success.
 */
int qcom_scm_pas_mem_setup(u32 peripheral, phys_addr_t addr, phys_addr_t size)
{
	int ret;
	struct qcom_scm_desc desc = {
		.svc = QCOM_SCM_SVC_PIL,
		.cmd = QCOM_SCM_PIL_PAS_MEM_SETUP,
		.arginfo = QCOM_SCM_ARGS(3),
		.args[0] = peripheral,
		.args[1] = addr,
		.args[2] = size,
		.owner = ARM_SMCCC_OWNER_SIP,
	};
	struct qcom_scm_res res;

	ret = qcom_scm_clk_enable();
	if (ret)
		return ret;

	ret = qcom_scm_call(__scm->dev, &desc, &res);
	qcom_scm_clk_disable();

	return ret ? : res.result[0];
}
EXPORT_SYMBOL(qcom_scm_pas_mem_setup);

/**
 * qcom_scm_pas_auth_and_reset() - Authenticate the given peripheral firmware
 *				   and reset the remote processor
 * @peripheral:	peripheral id
 *
 * Return 0 on success.
 */
int qcom_scm_pas_auth_and_reset(u32 peripheral)
{
	int ret;
	struct qcom_scm_desc desc = {
		.svc = QCOM_SCM_SVC_PIL,
		.cmd = QCOM_SCM_PIL_PAS_AUTH_AND_RESET,
		.arginfo = QCOM_SCM_ARGS(1),
		.args[0] = peripheral,
		.owner = ARM_SMCCC_OWNER_SIP,
	};
	struct qcom_scm_res res;

	ret = qcom_scm_clk_enable();
	if (ret)
		return ret;

	ret = qcom_scm_call(__scm->dev, &desc, &res);
	qcom_scm_clk_disable();

	return ret ? : res.result[0];
}
EXPORT_SYMBOL(qcom_scm_pas_auth_and_reset);

/**
 * qcom_scm_pas_shutdown() - Shut down the remote processor
 * @peripheral: peripheral id
 *
 * Returns 0 on success.
 */
int qcom_scm_pas_shutdown(u32 peripheral)
{
	int ret;
	struct qcom_scm_desc desc = {
		.svc = QCOM_SCM_SVC_PIL,
		.cmd = QCOM_SCM_PIL_PAS_SHUTDOWN,
		.arginfo = QCOM_SCM_ARGS(1),
		.args[0] = peripheral,
		.owner = ARM_SMCCC_OWNER_SIP,
	};
	struct qcom_scm_res res;

	ret = qcom_scm_clk_enable();
	if (ret)
		return ret;

	ret = qcom_scm_call(__scm->dev, &desc, &res);

	qcom_scm_clk_disable();

	return ret ? : res.result[0];
}
EXPORT_SYMBOL(qcom_scm_pas_shutdown);

/**
 * qcom_scm_pas_supported() - Check if the peripheral authentication service is
 *			      available for the given peripherial
 * @peripheral:	peripheral id
 *
 * Returns true if PAS is supported for this peripheral, otherwise false.
 */
bool qcom_scm_pas_supported(u32 peripheral)
{
	int ret;
	struct qcom_scm_desc desc = {
		.svc = QCOM_SCM_SVC_PIL,
		.cmd = QCOM_SCM_PIL_PAS_IS_SUPPORTED,
		.arginfo = QCOM_SCM_ARGS(1),
		.args[0] = peripheral,
		.owner = ARM_SMCCC_OWNER_SIP,
	};
	struct qcom_scm_res res;

	ret = __qcom_scm_is_call_available(__scm->dev, QCOM_SCM_SVC_PIL,
					   QCOM_SCM_PIL_PAS_IS_SUPPORTED);
	if (ret <= 0)
		return false;

	ret = qcom_scm_call(__scm->dev, &desc, &res);

	return ret ? false : !!res.result[0];
}
EXPORT_SYMBOL(qcom_scm_pas_supported);

static int __qcom_scm_pas_mss_reset(struct device *dev, bool reset)
{
	struct qcom_scm_desc desc = {
		.svc = QCOM_SCM_SVC_PIL,
		.cmd = QCOM_SCM_PIL_PAS_MSS_RESET,
		.arginfo = QCOM_SCM_ARGS(2),
		.args[0] = reset,
		.args[1] = 0,
		.owner = ARM_SMCCC_OWNER_SIP,
	};
	struct qcom_scm_res res;
	int ret;

	ret = qcom_scm_call(__scm->dev, &desc, &res);

	return ret ? : res.result[0];
}

static int qcom_scm_pas_reset_assert(struct reset_controller_dev *rcdev,
				     unsigned long idx)
{
	if (idx != 0)
		return -EINVAL;

	return __qcom_scm_pas_mss_reset(__scm->dev, 1);
}

static int qcom_scm_pas_reset_deassert(struct reset_controller_dev *rcdev,
				       unsigned long idx)
{
	if (idx != 0)
		return -EINVAL;

	return __qcom_scm_pas_mss_reset(__scm->dev, 0);
}

static const struct reset_control_ops qcom_scm_pas_reset_ops = {
	.assert = qcom_scm_pas_reset_assert,
	.deassert = qcom_scm_pas_reset_deassert,
};

int qcom_scm_io_readl(phys_addr_t addr, unsigned int *val)
{
	struct qcom_scm_desc desc = {
		.svc = QCOM_SCM_SVC_IO,
		.cmd = QCOM_SCM_IO_READ,
		.arginfo = QCOM_SCM_ARGS(1),
		.args[0] = addr,
		.owner = ARM_SMCCC_OWNER_SIP,
	};
	struct qcom_scm_res res;
	int ret;


	ret = qcom_scm_call(__scm->dev, &desc, &res);
	if (ret >= 0)
		*val = res.result[0];

	return ret < 0 ? ret : 0;
}
EXPORT_SYMBOL(qcom_scm_io_readl);

int qcom_scm_io_writel(phys_addr_t addr, unsigned int val)
{
	struct qcom_scm_desc desc = {
		.svc = QCOM_SCM_SVC_IO,
		.cmd = QCOM_SCM_IO_WRITE,
		.arginfo = QCOM_SCM_ARGS(2),
		.args[0] = addr,
		.args[1] = val,
		.owner = ARM_SMCCC_OWNER_SIP,
	};


	return qcom_scm_call(__scm->dev, &desc, NULL);
}
EXPORT_SYMBOL(qcom_scm_io_writel);

/**
 * qcom_scm_restore_sec_cfg_available() - Check if secure environment
 * supports restore security config interface.
 *
 * Return true if restore-cfg interface is supported, false if not.
 */
bool qcom_scm_restore_sec_cfg_available(void)
{
	return __qcom_scm_is_call_available(__scm->dev, QCOM_SCM_SVC_MP,
					    QCOM_SCM_MP_RESTORE_SEC_CFG);
}
EXPORT_SYMBOL(qcom_scm_restore_sec_cfg_available);

int qcom_scm_restore_sec_cfg(u32 device_id, u32 spare)
{
	struct qcom_scm_desc desc = {
		.svc = QCOM_SCM_SVC_MP,
		.cmd = QCOM_SCM_MP_RESTORE_SEC_CFG,
		.arginfo = QCOM_SCM_ARGS(2),
		.args[0] = device_id,
		.args[1] = spare,
		.owner = ARM_SMCCC_OWNER_SIP,
	};
	struct qcom_scm_res res;
	int ret;

	ret = qcom_scm_call(__scm->dev, &desc, &res);

	return ret ? : res.result[0];
}
EXPORT_SYMBOL(qcom_scm_restore_sec_cfg);

int qcom_scm_iommu_secure_ptbl_size(u32 spare, size_t *size)
{
	struct qcom_scm_desc desc = {
		.svc = QCOM_SCM_SVC_MP,
		.cmd = QCOM_SCM_MP_IOMMU_SECURE_PTBL_SIZE,
		.arginfo = QCOM_SCM_ARGS(1),
		.args[0] = spare,
		.owner = ARM_SMCCC_OWNER_SIP,
	};
	struct qcom_scm_res res;
	int ret;

	ret = qcom_scm_call(__scm->dev, &desc, &res);

	if (size)
		*size = res.result[0];

	return ret ? : res.result[1];
}
EXPORT_SYMBOL(qcom_scm_iommu_secure_ptbl_size);

int qcom_scm_iommu_secure_ptbl_init(u64 addr, u32 size, u32 spare)
{
	struct qcom_scm_desc desc = {
		.svc = QCOM_SCM_SVC_MP,
		.cmd = QCOM_SCM_MP_IOMMU_SECURE_PTBL_INIT,
		.arginfo = QCOM_SCM_ARGS(3, QCOM_SCM_RW, QCOM_SCM_VAL,
					 QCOM_SCM_VAL),
		.args[0] = addr,
		.args[1] = size,
		.args[2] = spare,
		.owner = ARM_SMCCC_OWNER_SIP,
	};
	int ret;

	desc.args[0] = addr;
	desc.args[1] = size;
	desc.args[2] = spare;
	desc.arginfo = QCOM_SCM_ARGS(3, QCOM_SCM_RW, QCOM_SCM_VAL,
				     QCOM_SCM_VAL);

	ret = qcom_scm_call(__scm->dev, &desc, NULL);

	/* the pg table has been initialized already, ignore the error */
	if (ret == -EPERM)
		ret = 0;

	return ret;
}
EXPORT_SYMBOL(qcom_scm_iommu_secure_ptbl_init);

static int __qcom_scm_assign_mem(struct device *dev, phys_addr_t mem_region,
				 size_t mem_sz, phys_addr_t src, size_t src_sz,
				 phys_addr_t dest, size_t dest_sz)
{
	int ret;
	struct qcom_scm_desc desc = {
		.svc = QCOM_SCM_SVC_MP,
		.cmd = QCOM_SCM_MP_ASSIGN,
		.arginfo = QCOM_SCM_ARGS(7, QCOM_SCM_RO, QCOM_SCM_VAL,
					 QCOM_SCM_RO, QCOM_SCM_VAL, QCOM_SCM_RO,
					 QCOM_SCM_VAL, QCOM_SCM_VAL),
		.args[0] = mem_region,
		.args[1] = mem_sz,
		.args[2] = src,
		.args[3] = src_sz,
		.args[4] = dest,
		.args[5] = dest_sz,
		.args[6] = 0,
		.owner = ARM_SMCCC_OWNER_SIP,
	};
	struct qcom_scm_res res;

	ret = qcom_scm_call(dev, &desc, &res);

	return ret ? : res.result[0];
}

/**
 * qcom_scm_assign_mem() - Make a secure call to reassign memory ownership
 * @mem_addr: mem region whose ownership need to be reassigned
 * @mem_sz:   size of the region.
 * @srcvm:    vmid for current set of owners, each set bit in
 *            flag indicate a unique owner
 * @newvm:    array having new owners and corresponding permission
 *            flags
 * @dest_cnt: number of owners in next set.
 *
 * Return negative errno on failure or 0 on success with @srcvm updated.
 */
int qcom_scm_assign_mem(phys_addr_t mem_addr, size_t mem_sz,
			unsigned int *srcvm,
			const struct qcom_scm_vmperm *newvm,
			unsigned int dest_cnt)
{
	struct qcom_scm_current_perm_info *destvm;
	struct qcom_scm_mem_map_info *mem_to_map;
	phys_addr_t mem_to_map_phys;
	phys_addr_t dest_phys;
	phys_addr_t ptr_phys;
	dma_addr_t ptr_dma;
	size_t mem_to_map_sz;
	size_t dest_sz;
	size_t src_sz;
	size_t ptr_sz;
	int next_vm;
	__le32 *src;
	void *ptr;
	int ret, i, b;
	unsigned long srcvm_bits = *srcvm;

	src_sz = hweight_long(srcvm_bits) * sizeof(*src);
	mem_to_map_sz = sizeof(*mem_to_map);
	dest_sz = dest_cnt * sizeof(*destvm);
	ptr_sz = ALIGN(src_sz, SZ_64) + ALIGN(mem_to_map_sz, SZ_64) +
			ALIGN(dest_sz, SZ_64);

	ptr = dma_alloc_coherent(__scm->dev, ptr_sz, &ptr_dma, GFP_KERNEL);
	if (!ptr)
		return -ENOMEM;
	ptr_phys = dma_to_phys(__scm->dev, ptr_dma);

	/* Fill source vmid detail */
	src = ptr;
	i = 0;
	for_each_set_bit(b, &srcvm_bits, BITS_PER_LONG)
		src[i++] = cpu_to_le32(b);

	/* Fill details of mem buff to map */
	mem_to_map = ptr + ALIGN(src_sz, SZ_64);
	mem_to_map_phys = ptr_phys + ALIGN(src_sz, SZ_64);
	mem_to_map->mem_addr = cpu_to_le64(mem_addr);
	mem_to_map->mem_size = cpu_to_le64(mem_sz);

	next_vm = 0;
	/* Fill details of next vmid detail */
	destvm = ptr + ALIGN(mem_to_map_sz, SZ_64) + ALIGN(src_sz, SZ_64);
	dest_phys = ptr_phys + ALIGN(mem_to_map_sz, SZ_64) + ALIGN(src_sz, SZ_64);
	for (i = 0; i < dest_cnt; i++, destvm++, newvm++) {
		destvm->vmid = cpu_to_le32(newvm->vmid);
		destvm->perm = cpu_to_le32(newvm->perm);
		destvm->ctx = 0;
		destvm->ctx_size = 0;
		next_vm |= BIT(newvm->vmid);
	}

	ret = __qcom_scm_assign_mem(__scm->dev, mem_to_map_phys, mem_to_map_sz,
				    ptr_phys, src_sz, dest_phys, dest_sz);
	dma_free_coherent(__scm->dev, ptr_sz, ptr, ptr_dma);
	if (ret) {
		dev_err(__scm->dev,
			"Assign memory protection call failed %d\n", ret);
		return -EINVAL;
	}

	*srcvm = next_vm;
	return 0;
}
EXPORT_SYMBOL(qcom_scm_assign_mem);

/**
 * qcom_scm_ocmem_lock_available() - is OCMEM lock/unlock interface available
 */
bool qcom_scm_ocmem_lock_available(void)
{
	return __qcom_scm_is_call_available(__scm->dev, QCOM_SCM_SVC_OCMEM,
					    QCOM_SCM_OCMEM_LOCK_CMD);
}
EXPORT_SYMBOL(qcom_scm_ocmem_lock_available);

/**
 * qcom_scm_ocmem_lock() - call OCMEM lock interface to assign an OCMEM
 * region to the specified initiator
 *
 * @id:     tz initiator id
 * @offset: OCMEM offset
 * @size:   OCMEM size
 * @mode:   access mode (WIDE/NARROW)
 */
int qcom_scm_ocmem_lock(enum qcom_scm_ocmem_client id, u32 offset, u32 size,
			u32 mode)
{
	struct qcom_scm_desc desc = {
		.svc = QCOM_SCM_SVC_OCMEM,
		.cmd = QCOM_SCM_OCMEM_LOCK_CMD,
		.args[0] = id,
		.args[1] = offset,
		.args[2] = size,
		.args[3] = mode,
		.arginfo = QCOM_SCM_ARGS(4),
	};

	return qcom_scm_call(__scm->dev, &desc, NULL);
}
EXPORT_SYMBOL(qcom_scm_ocmem_lock);

/**
 * qcom_scm_ocmem_unlock() - call OCMEM unlock interface to release an OCMEM
 * region from the specified initiator
 *
 * @id:     tz initiator id
 * @offset: OCMEM offset
 * @size:   OCMEM size
 */
int qcom_scm_ocmem_unlock(enum qcom_scm_ocmem_client id, u32 offset, u32 size)
{
	struct qcom_scm_desc desc = {
		.svc = QCOM_SCM_SVC_OCMEM,
		.cmd = QCOM_SCM_OCMEM_UNLOCK_CMD,
		.args[0] = id,
		.args[1] = offset,
		.args[2] = size,
		.arginfo = QCOM_SCM_ARGS(3),
	};

	return qcom_scm_call(__scm->dev, &desc, NULL);
}
EXPORT_SYMBOL(qcom_scm_ocmem_unlock);

/**
 * qcom_scm_hdcp_available() - Check if secure environment supports HDCP.
 *
 * Return true if HDCP is supported, false if not.
 */
bool qcom_scm_hdcp_available(void)
{
	int ret = qcom_scm_clk_enable();

	if (ret)
		return ret;

	ret = __qcom_scm_is_call_available(__scm->dev, QCOM_SCM_SVC_HDCP,
						QCOM_SCM_HDCP_INVOKE);

	qcom_scm_clk_disable();

	return ret > 0 ? true : false;
}
EXPORT_SYMBOL(qcom_scm_hdcp_available);

/**
 * qcom_scm_hdcp_req() - Send HDCP request.
 * @req: HDCP request array
 * @req_cnt: HDCP request array count
 * @resp: response buffer passed to SCM
 *
 * Write HDCP register(s) through SCM.
 */
int qcom_scm_hdcp_req(struct qcom_scm_hdcp_req *req, u32 req_cnt, u32 *resp)
{
	int ret;
	struct qcom_scm_desc desc = {
		.svc = QCOM_SCM_SVC_HDCP,
		.cmd = QCOM_SCM_HDCP_INVOKE,
		.arginfo = QCOM_SCM_ARGS(10),
		.args = {
			req[0].addr,
			req[0].val,
			req[1].addr,
			req[1].val,
			req[2].addr,
			req[2].val,
			req[3].addr,
			req[3].val,
			req[4].addr,
			req[4].val
		},
		.owner = ARM_SMCCC_OWNER_SIP,
	};
	struct qcom_scm_res res;

	if (req_cnt > QCOM_SCM_HDCP_MAX_REQ_CNT)
		return -ERANGE;

	ret = qcom_scm_clk_enable();
	if (ret)
		return ret;

	ret = qcom_scm_call(__scm->dev, &desc, &res);
	*resp = res.result[0];

	qcom_scm_clk_disable();

	return ret;
}
EXPORT_SYMBOL(qcom_scm_hdcp_req);

int qcom_scm_qsmmu500_wait_safe_toggle(bool en)
{
	struct qcom_scm_desc desc = {
		.svc = QCOM_SCM_SVC_SMMU_PROGRAM,
		.cmd = QCOM_SCM_SMMU_CONFIG_ERRATA1,
		.arginfo = QCOM_SCM_ARGS(2),
		.args[0] = QCOM_SCM_SMMU_CONFIG_ERRATA1_CLIENT_ALL,
		.args[1] = en,
		.owner = ARM_SMCCC_OWNER_SIP,
	};


	return qcom_scm_call_atomic(__scm->dev, &desc, NULL);
}
EXPORT_SYMBOL(qcom_scm_qsmmu500_wait_safe_toggle);

static int qcom_scm_find_dload_address(struct device *dev, u64 *addr)
{
	struct device_node *tcsr;
	struct device_node *np = dev->of_node;
	struct resource res;
	u32 offset;
	int ret;

	tcsr = of_parse_phandle(np, "qcom,dload-mode", 0);
	if (!tcsr)
		return 0;

	ret = of_address_to_resource(tcsr, 0, &res);
	of_node_put(tcsr);
	if (ret)
		return ret;

	ret = of_property_read_u32_index(np, "qcom,dload-mode", 1, &offset);
	if (ret < 0)
		return ret;

	*addr = res.start + offset;

	return 0;
}

/**
 * qcom_scm_is_available() - Checks if SCM is available
 */
bool qcom_scm_is_available(void)
{
	return !!__scm;
}
EXPORT_SYMBOL(qcom_scm_is_available);

static int qcom_scm_probe(struct platform_device *pdev)
{
	struct qcom_scm *scm;
	unsigned long clks;
	int ret;

	scm = devm_kzalloc(&pdev->dev, sizeof(*scm), GFP_KERNEL);
	if (!scm)
		return -ENOMEM;

	ret = qcom_scm_find_dload_address(&pdev->dev, &scm->dload_mode_addr);
	if (ret < 0)
		return ret;

	clks = (unsigned long)of_device_get_match_data(&pdev->dev);

	scm->core_clk = devm_clk_get(&pdev->dev, "core");
	if (IS_ERR(scm->core_clk)) {
		if (PTR_ERR(scm->core_clk) == -EPROBE_DEFER)
			return PTR_ERR(scm->core_clk);

		if (clks & SCM_HAS_CORE_CLK) {
			dev_err(&pdev->dev, "failed to acquire core clk\n");
			return PTR_ERR(scm->core_clk);
		}

		scm->core_clk = NULL;
	}

	scm->iface_clk = devm_clk_get(&pdev->dev, "iface");
	if (IS_ERR(scm->iface_clk)) {
		if (PTR_ERR(scm->iface_clk) == -EPROBE_DEFER)
			return PTR_ERR(scm->iface_clk);

		if (clks & SCM_HAS_IFACE_CLK) {
			dev_err(&pdev->dev, "failed to acquire iface clk\n");
			return PTR_ERR(scm->iface_clk);
		}

		scm->iface_clk = NULL;
	}

	scm->bus_clk = devm_clk_get(&pdev->dev, "bus");
	if (IS_ERR(scm->bus_clk)) {
		if (PTR_ERR(scm->bus_clk) == -EPROBE_DEFER)
			return PTR_ERR(scm->bus_clk);

		if (clks & SCM_HAS_BUS_CLK) {
			dev_err(&pdev->dev, "failed to acquire bus clk\n");
			return PTR_ERR(scm->bus_clk);
		}

		scm->bus_clk = NULL;
	}

	scm->reset.ops = &qcom_scm_pas_reset_ops;
	scm->reset.nr_resets = 1;
	scm->reset.of_node = pdev->dev.of_node;
	ret = devm_reset_controller_register(&pdev->dev, &scm->reset);
	if (ret)
		return ret;

	/* vote for max clk rate for highest performance */
	ret = clk_set_rate(scm->core_clk, INT_MAX);
	if (ret)
		return ret;

	__scm = scm;
	__scm->dev = &pdev->dev;

	__query_convention();

	/*
	 * If requested enable "download mode", from this point on warmboot
	 * will cause the the boot stages to enter download mode, unless
	 * disabled below by a clean shutdown/reboot.
	 */
	if (download_mode)
		qcom_scm_set_download_mode(true);

	return 0;
}

static void qcom_scm_shutdown(struct platform_device *pdev)
{
	/* Clean shutdown, disable download mode to allow normal restart */
	if (download_mode)
		qcom_scm_set_download_mode(false);
}

static const struct of_device_id qcom_scm_dt_match[] = {
	{ .compatible = "qcom,scm-apq8064",
	  /* FIXME: This should have .data = (void *) SCM_HAS_CORE_CLK */
	},
	{ .compatible = "qcom,scm-apq8084", .data = (void *)(SCM_HAS_CORE_CLK |
							     SCM_HAS_IFACE_CLK |
							     SCM_HAS_BUS_CLK)
	},
	{ .compatible = "qcom,scm-ipq4019" },
	{ .compatible = "qcom,scm-msm8660", .data = (void *) SCM_HAS_CORE_CLK },
	{ .compatible = "qcom,scm-msm8960", .data = (void *) SCM_HAS_CORE_CLK },
	{ .compatible = "qcom,scm-msm8916", .data = (void *)(SCM_HAS_CORE_CLK |
							     SCM_HAS_IFACE_CLK |
							     SCM_HAS_BUS_CLK)
	},
	{ .compatible = "qcom,scm-msm8974", .data = (void *)(SCM_HAS_CORE_CLK |
							     SCM_HAS_IFACE_CLK |
							     SCM_HAS_BUS_CLK)
	},
	{ .compatible = "qcom,scm-msm8996" },
	{ .compatible = "qcom,scm" },
	{}
};

static struct platform_driver qcom_scm_driver = {
	.driver = {
		.name	= "qcom_scm",
		.of_match_table = qcom_scm_dt_match,
	},
	.probe = qcom_scm_probe,
	.shutdown = qcom_scm_shutdown,
};

static int __init qcom_scm_init(void)
{
	return platform_driver_register(&qcom_scm_driver);
}
subsys_initcall(qcom_scm_init);